This invention relates to a device for controlling the balloon and tension in the thread from a storing and distributing apparatus to an operating machine.
As is well known in the art, many operating machines, such as weaving machines, are not directly supplied with yarn from a bobbin, cop or the like, but such a yarn from the bobbin reaches the operating machine after being previously wound on an apparatus, where a magazine or supply yarn is formed. The yarn is then supplied to utilization with constant controlled tension.
One being drawn from these storing apparatus, the yarn unwinds at a very high speed at the periphery of a drum, on which it is wound in turns. Many types of devices have been proposed for imparting a predetermined rate of tension to the yarn unwinding from the drum. However, it was found that, although being effective in imparting a predetermined rate of tension to the yarn unwinding from the drum, these devices are not versatile. Thus, they do not allow adjusting the tension to rates that vary with time.
Furthermore, the risk very often occurs that the thread unwinding from the drum would form balloons due to centrifugal force, or would tend to be moved away from the drum to a high extent, thus preventing any control of outlet speed and yarn tension.
It is the primary object of the present invention to provide a device of simple structure and low cost of production, which is readily applicable to known type of thread storing apparatus. The device is to enable controlling the balloon of the thread unwinding from the apparatus to which such a device is applied, and also to enable controlling the tension of the yarn supplied to an operating machine at a constant rate and extent that can be easily and readily varied.